Fan structure

ABSTRACT

A fan structure includes a sleeve, an impeller, a bearing and a fixing shaft, wherein the sleeve is covered with a hub of the impeller. The sleeve comprises a ring wall, an accommodating slot and a top portion, and a penetration hole is formed at the top portion. The bearing is disposed at the accommodating slot and comprises an axial hole and a top surface, wherein the top surface of the bearing and the top portion are spaced apart from each other by an interval. The fixing shaft penetrates through the axial hole of the bearing, a free end of the fixing shaft is protruded to the top portion via the penetration hole, and an oil storage space can be defined between the top portion of the sleeve, the top surface of the bearing and the fixing shaft. Mentioned oil storage space may prevent lubricants from splashing

FIELD OF THE INVENTION

The present invention is generally related to a fan structure, which particularly relates to the fan structure that prevents lubricants from attaching to a top portion of a sleeve to avoid lubricants from splashing.

BACKGROUND OF THE INVENTION

With reference to FIG. 4, a conventional fan structure 10 includes an impeller 11, a bearing 12, a fixing shaft 13, a cap 14 and a base 15, wherein the impeller 11 comprises a hub 11 a, a sleeve 11 b and an accommodating slot 11 c. The hub 11 a and the sleeve 11 b are formed as one piece, the accommodating slot 11 c is recessed from the sleeve 11 b, the bearing 12 is accommodated within the accommodating slot 11 c, and the bearing 12 is in contact against the hub 11 a. The hub 11 a comprises a penetration hole 11 d, and an axial hole 12 a of the bearing 12 is connected to the penetration hole 11 d. The fixing shaft 13 penetrates through the axial hole 12 a, a free end 13 a of the fixing shaft 13 penetrates through the axial hole 12 a of the bearing 12 and the penetration hole 11 d of the hub 11 a, and the free end 13 a is protruded to the hub 11 a. A fixing end 13 b of the fixing shaft 13 couples to the cap 14, and the cap 14 is coupled to the base 15. The fixing shaft 13 enables to prevent a case 21 (or a keyboard) of an electrical goods 20 from compressing the impeller 11 to avoid a destruction of the fan structure 10. However, when the impeller 11 is driven to rotate by a stator 16, lubricants utilized for lubricating the bearing 12 may pass through the penetration hole 11 d of the hub 11 a and splashes out via a centrifugal force of rotating impeller 11 owning to the reason that the axial hole 12 a of the bearing 12 and the penetration hole 11 d of the hub 11 a are interconnected. Therefore, the friction between the fixing shaft 13 and the bearing 12 increases substantially so as to reduce the lifetime of the fan structure 10.

SUMMARY

The primary object of the present invention is to provide a fan structure. In the fan structure, an interval between a top surface of a bearing and a top portion of a sleeve for making an oil storage space defined between the top portion of the sleeve, the top surface of the bearing and a fixing shaft. The oil storage space enables to prevent lubricants for lubricating the bearing from attaching to the top portion of the sleeve to avoid lubricants splashed from a penetration hole of the top portion.

The fan structure includes a cap, a sleeve, an impeller, a bearing and a fixing shaft, wherein the cap comprises an accommodating space, and the sleeve comprises a ring wall, an accommodating slot surrounded by the ring wall and a top portion in connection with the ring wall. A penetration hole communicated with the accommodating slot is formed at the top portion. The ring wall of the sleeve is accommodated within the accommodating space of the cap. The impeller comprises a hub covering the sleeve. The bearing is disposed within the accommodating slot of the sleeve and comprises an axial hole and a top surface facing toward the top portion of the sleeve. The top surface of the bearing and the top portion of the sleeve are spaced apart from each other by an interval. The fixing shaft penetrates through the axial hole of the bearing and comprises a free end and a fixing end coupled to the cap, wherein the free end is protruded to the top portion via the penetration hole, and an oil storage space can be defined between the top portion of the sleeve, the top surface of the bearing and the fixing shaft. Mentioned oil storage space enables to prevent lubricants for lubricating the bearing from attaching to the top portion of the sleeve to avoid lubricants splashed from the penetration hole of the top portion.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a section view illustrating a fan structure in accordance with a first embodiment of the present invention.

FIG. 2 is a partial enlargement diagram illustrating a fan structure in accordance with a first embodiment of the present invention.

FIG. 3 is a section view illustrating a fan structure in accordance with a second embodiment of the present invention.

FIG. 4 is a section view illustrating a conventional fan structure.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, a fan structure 100 in accordance with a first preferred embodiment of the present invention includes sleeve 110, an impeller 120, a bearing 130, a fixing shaft 140, a cap 150, a stator 160, a base 170 and a circuit board 180. The cap 150 and the circuit board 180 are disposed on the base 170, and the stator 160 is coupled to the cap 150 for driving the impeller 120 into rotation. In this embodiment, the material of the sleeve 110 is different from that of the impeller 120. Referring to FIGS. 1 and 2, the sleeve 110 is preformed and comprises a ring wall 111, a first lodge portion 112 formed on the ring wall 111, an accommodating slot 113 surrounded by the ring wall 111 and a top portion 114 in connection with the ring wall 111, wherein a penetration hole 114 a is formed at the top portion 114 and communicates with the accommodating slot 113. The penetration hole 114 a comprises a surface 114 b, and the top portion 114 comprises an interior surface 114 c in connection with the surface 114 b. In this embodiment, the sleeve 110 is cladded by the impeller 120 by means of injection molding. The impeller 120 comprises a hub 121 and a plurality of blades 122 in connection with the hub 121. In the process of injection molding the impeller 120, the sleeve 110 is cladded by the hub 121 simultaneously, wherein a second lodge portion 123 is formed at the hub 121 as to make the first lodge portion 112 cladded by the second lodge portion 123. In this embodiment, the first lodge portion 112 comprises a first protrusion 112 a and a second recess 112 b, the second lodge portion 123 comprises a first recess 123 a and a second protrusion 123 b cladded by the second recess 112 b, and the first protrusion 112 a is cladded by the first recess 123 a. With reference to FIGS. 1 and 2, the bearing 130 is disposed at the accommodating slot 113 of the sleeve 110 and comprises an axial hole 131 and a top surface 132 facing toward the top portion 114 of the sleeve 110. The top surface 132 of the bearing 130 and the top portion 114 of the sleeve 110 are spaced apart from each other by an interval D. The fixing shaft 140 penetrates through axial hole 131 of the bearing 130 and comprises a fixing end 141, a free end 142, a slot 143 and an oil storage vessel 144. The free end 142 of the fixing shaft 140 is protruded to the top portion 114 via the penetration hole 114 a, and the fixing end 141 is fixedly disposed on the cap 150. In this embodiment, the cap 150 comprises a bottom portion 151 and an accommodating space 152, the fixing end 141 is fixedly disposed on the bottom portion 151 of the cap 150, the bearing 130 and the ring wall 111 of the sleeve 110 are accommodated within the accommodating space 152. An oil storage space S can be defined between the top portion 114 of the sleeve 110, the top surface 132 of the bearing 130 and the fixing shaft 140. The slot 143 of the fixing shaft 140 communicates with the oil storage space S, and the oil storage vessel 144 is located inside the axial hole 131.

Please refer to FIGS. 1 and 2, when the impeller 120 is driven to rotate by the stator 160, lubricants for lubricating the bearing 130 flow upwardly along the axial hole 131 of the bearing 130 and the fixing shaft 140. Once lubricants flow into the oil storage vessel 144 of the fixing shaft 140, lubricants can be stored within the oil storage vessel 144 for the reason that the surface of the fixing shaft 140 is formed as the surface of discontinuity.

Please refer to FIGS. 1 and 2 again, when part of the lubricants flow upwardly to the top surface 132 of the bearing 130, lubricants can be collected inside the oil storage space S and the slot 143 of the fixing shaft 140 through a centrifugal force of the impeller 120 and the bearing 130 (rather than flowing toward the interior surface 114 c of the top portion 114 and the surface 114 b of the penetration hole 114 a) owning to the interval D between the top surface 132 and the top portion 114, which prevents lubricants from attaching to the top portion 114 of the sleeve 110 to avoid lubricants splashed from the penetration hole 114 a of the top portion 114.

With reference to FIGS. 1 and 2, the ring wall 111 of the sleeve 110 comprises an inner surface 111 a and an outer surface 111 b, the fan structure 100 further includes a stirring layer L formed on the inner surface 111 a of the ring wall 111, the surface 114 b of the penetration hole 114 a, the top portion 114 of the interior surface 114 c , the top surface 132 of the bearing 130 and the slot 143 of the fixing shaft 140 to prevent lubricants from attaching to the slot 143 of the fixing shaft 140 and the sleeve 110 to avoid lubricants from splashing

A second preferred embodiment of the present invention is illustrated in

FIG. 3, the primary difference between the first embodiment and the second embodiment is that the fan structure 100 further includes a limiting member 190, the limiting member 190 is disposed within the oil storage space S, fastened at the slot 143 of the fixing shaft 140, and located between the top portion 114 of the sleeve 110 and the bearing 130. The limiting member 190 is utilized for preventing the impeller 120 from falling off. Besides, the ring wall 111 comprises a blocking member 111 c disposed on the inner surface 111 a, and the ring wall 111 can be a slot recessed from the inner surface 111 a or a projecting rib (or a bump) protruded to the inner surface 111 a. In this embodiment, the blocking member 111 c is protruded to the inner surface 111 a of the ring wall 111, and the blocking member 111 c is ring shaped. The bearing 130 is in contact against the blocking member 111 c. When the bearing 130 is installed inside the sleeve 110, the blocking member 111 c is provided to keep the top surface 132 of the bearing 130 from excessively approaching the top portion 114 of the sleeve 110 to avoid lubricants splashed from the penetration hole 114 a of the top portion 114.

When the impeller 120 is into rotation, lubricants utilized for lubricating the bearing 130 can be collected within the oil storage space S and the slot 143 of the fixing shaft 140 via a centrifugal force of the impeller 120 and the bearing 130, which prevents lubricants from flowing toward the free end 142 of the fixing shaft 140 and the penetration hole 114 a of the top portion 114 to avoid lubricants from splashing Therefore, mentioned lubricants enable to be recycled in the fan structure 100 for reclamation so that the lifetime of the fan structure 100 can be effectively increased. While this invention has been particularly illustrated and described in detail with respect to the preferred embodiments thereof, it will be clearly understood by those skilled in the art that it is not limited to the specific features and describes and various modifications and changes in form and details may be made without departing from the spirit and scope of this invention. 

What is claimed is:
 1. A fan structure including: a cap having an accommodating space; a sleeve having a ring wall, an accommodating slot surrounded by the ring wall and a top portion in connection with the ring wall, wherein a penetration hole communicated with the accommodating slot is formed at the top portion, and the ring wall is accommodated within the accommodating space of the cap; an impeller having a hub for covering the sleeve; a bearing having an axial hole and a top surface facing toward the top portion of the sleeve, the bearing is disposed at the accommodating slot of the sleeve, the top surface and the top portion are spaced apart from each other by an interval; and a fixing shaft having a free end protruded to the top portion via the penetration hole and a fixing end coupled to the cap, wherein the fixing shaft penetrates through the axial hole of the bearing, and an oil storage space can be defined between the top portion of the sleeve, the top surface of the bearing and the fixing shaft.
 2. The fan structure in accordance with claim 1, wherein the fixing shaft further comprises a slot in communication with the oil storage space.
 3. The fan structure in accordance with claim 1, wherein the sleeve comprises a first lodge portion formed at the ring wall, the hub of the impeller comprises a second lodge portion, and the first lodge portion is cladded by the second lodge portion.
 4. The fan structure in accordance with claim 3, wherein the first lodge portion comprises a first protrusion, the second lodge portion comprises a first recess, and the first protrusion is cladded by the first recess.
 5. The fan structure in accordance with claim 4, wherein the first lodge portion comprises a second recess, the second lodge portion comprises a second protrusion cladded by the second recess.
 6. The fan structure in accordance with claim 3, wherein the first lodge portion comprises a second recess, the second lodge portion comprises a second protrusion cladded by the second recess.
 7. The fan structure in accordance with claim 2 further includes a limiting member fastened at the slot of the fixing shaft, wherein the limiting member is located between the top portion and the bearing.
 8. The fan structure in accordance with claim 1 further includes a stirring layer, wherein the ring wall comprises an inner surface, and the stirring layer is formed on the inner surface.
 9. The fan structure in accordance with claim 1 further includes a stirring layer, wherein the top portion comprises an interior surface, and the stirring layer is formed on the interior surface.
 10. The fan structure in accordance with claim 1 further includes a stirring layer formed on the top surface of the bearing.
 11. The fan structure in accordance with claim 2 further includes a stirring layer formed at the slot of the fixing shaft.
 12. The fan structure in accordance with claim 3, wherein the first lodge portion of the sleeve is cladded by the second lodge portion of the impeller by means of injection molding.
 13. The fan structure in accordance with claim 1, wherein the material of the sleeve is different from that of the impeller.
 14. The fan structure in accordance with claim 1, wherein the ring wall comprises an inner surface and a blocking member disposed on the inner surface.
 15. The fan structure in accordance with claim 14, wherein the bearing is in contact against the blocking member.
 16. The fan structure in accordance with claim 14, wherein the blocking member is protruded to the inner surface of the ring wall, and the blocking member is ring shaped. 